Evaluation of the Load Bearing Capacity of Piles by Numerical, Analytical and Empirical Approaches

Abstract

The evaluation of axial bearing capacity of piles plays an essential role in foundation design. It can be estimated by theoretical methods, through an analytical or numerical solution, or by semi-empirical methods, whose application is generally based on field test results. Semi-empirical formulations are often preferred by geotechnical engineers since theoretical approaches are generally limited to particular applications. This paper compares the axial bearing capacity of bored piles estimated by different methodologies, based on instrumented load tests carried out in the Campinas and the Brasilia university campi, in Brazil. The semi-empirical approach involved settlement control and extrapolation of load-settlement curve while the theoretical approach was based on both analytical and numerical solutions, the latter computed through finite element analyses. When compared to the bearing capacity measured in the instrumented load tests, both numerical and the settlement control results showed close agreement, while the extrapolation of the load-settlement curve estimated higher than expected results and the theoretical method presented conservative values when introducing the negative skin friction effects.